How about China putting on pressure on Rio to lower prices on the metals it sells to China and if Rio's share price drops a bit then why not China buying into Rio to gain even more influence on the corporation.
This is not much different than Putin shutting of oil or gas supplies to Europe to get his way. Or the US putting pressure on China to raise the value of it's money instead of the Americans devaluing their own due to over whelming debt.

Not just metals but it is all about power politics and global corporations are playing the game with even the largest of countries.

A question needs to be asked - If Rio Tinto's staff accepted bribes and are to be punished for it, then where are the one's that offered the bribes? Are they not just as guilty, more so in my opinion.
Could it be that the offerers of hose bribes are close to Chinese government?

I'm just tickled with all the possibilities. Beats soap operas hands down.